The Nelso Praga (Italian version) iPhone app started climbing the charts in Italy leading up to Christmas, and on New Year's Day it had hit #16 in the Travel category.
This has far exceeded our expectations. It's well known that a lot of Italians come to Prague for New Year's Eve, but because our app is specific just to the city of Prague (unlike, say, a translation app or currency convertor that might be downloaded by travelers going to any city), we were hoping only to rank in the Top 100 for travel apps, not to break the Top 20 and appear on the first page of the Travel section. Having the only free app in Italian for the search term "Praga" doesn't hurt, of course, but it's still (to us) a surprising result.
Needless to say, this has encouraged us to continue improving the Prague app, and to release similar apps for other cities. We'll be submitting an app for Copenhagen this week, and apps for other European cities later in January.